Ice tray



.1. H. ROETHEL IcE 2 Sheets-Sheet 1 Filed llarch 25 1948 JNVENTom #inl J. H. ROETHEL Feb. 28, 1950 ICE 'RAY 2 Shets-Sheet 2 Filed larch 25, 1948 MI kmq" IN VEN TOR. 7g/5,7 /71 WMZ/:feg

Patented Feb. 28, 1950 UNITEI) STATES PATENT OFFICE ICE TRAY John H.

I Boethel Mich., a corporation of Application March 25,1948, Serial No. 16,979`

sClaims.

This invention relates to liquid freezing trays and particularly, although not exclusively. to ice trays of the general type having a pan-like tray within which the ice cubes or blocks of frozen .substances are molded through the medium of a removable gridv member'V receivable within .the

tray.

kinds, eachv utilizing. an valuminumpan' within which the grid or divider is mounted. *One-such kind involves the use of a rigidly connected metal grid or divider necessitating the use of warm water to loosen not only the divider with its ice cubesfrom the pan but also the cubes from the divider. A second kind involves the use of an integral rubber grid or divider, trays of this Icetrays of the floregoingltype commonly 'usedf in refrigerators .have been of three principal kind also requiring water to be run over the pan-toloosen-the grid :and its rcubes after which the cubes' can lbe 0broken* loose. from fthe. rubber grid-only with considerable trouble.

the grid loose from the pan,'such trays presentingnot onlythe disadvantageof relatively high I cost of manufacture but also disadvantages due to frequent breakage of the levers at their pivotalv Roethel, Detroit, Mich., assignor to g Corporation, Detroit,

Michigan (CL (i2-108.5)

requisite-number of cubes detached therefrom without requiring any appreciable eii'ort, or necessitating thefuse .of warml water or levers to .free the ice cubes. as. heretofore.

Another object of the invention is toprovide an ice tray or the like having its pan and removable grid orA divider molded with a relatively thn highly flexible bottom wall from polyethylene plastic or the like, such material being of such character as to inhibit any appreciable adhesion of the ice thereto and, hence, enabling y easy release of the ice cubes, the vpan preferably Thel third -`kind Aof -ice .tray above referredv to involves the 1 :use of an articulated metal-gridand. leverto .break connections with'the' grids and, inaddition, the y frequent shattering of-the ice cubes when loosened by operation of the levers.

An important object of the present invention is to provide an ice tray or the like of the pan and grid type which overcomes. the principal vdisadvantages o f trays of-'this general type now or heretofore used, especially trays ofthe three types above mentioned, and in pursuance of such object to provide an ice tray of this type wherein both the pan and the separable grid or divider are both molded from plastic material, namely, polyethylene plastic or the equivalent, and so constructed as to be self-sustaining while at the same time enabling the grid and its cubes to be easily loosened from the pan and the cubes easily removed or freed individually or collectively from the grid or divider members.

4A further object of the invention is to form the pan of polyethylene or equivalent plastic material so that the bottom is relatively thin in order to accelerate the freezing rate, the bottom and side walls being so formed as to make the pan self-sustaining when filled with water, the preferred construction being such as to utilize the maximum amount of space within the pan for ice cubes while at the same time ensuring being formed with longitudinal and-.transverse stiifening'rrbs :disposed preferably "for, `engagement by the lower edges of the divider members and vthe latter preferably being so formed as to permit and facilitate removal of the icercubes without necessitating removal of the .divider lmembers by applying pressure to the bottom of the` tray to eject the cubes therefrom.

Other objects of this invention will 'appear in the following description and appended claims,

reference being had to the accompanying draw- 1 I ings forming a part of this specification wherein ,like reference characters designate corresponding parts in the several views.

Fig. 1 is a plan view of an ice tray embodyingV the present invention. y

Fig. 2 is a vsectional view taken substantially through lines 2-2 of Fig. 1 looking in the direction of the arrows.

Fig. 3 is a section taken substantially through lines 3-3 of Fig. 1 looking in the direction of the arrows.

Fig. 4 is a perspective view of the grid or dividing member. y

Fig. 5 is an end view of the grid or dividing member.

Before explaining in detail the present invention it is to be understood that the invention is not limited in its application to the details of construction and arrangement of parts illustrated in the accompanying drawings, since 'the invention is capable of other embodiments and of being practiced or carried out in various ways. Also it is to be understood that the phraseology or terminology employed herein is for the purpose of desumcient rigidity or strength in the pan to prescription and not of limitation.

In the drawings there is illustrated, by way of example, an ice tray comprising a pan-like receptacle adaptedto contain water and constructed to receive a removable grid or dividing member by means of which a number of ice cubes or blocks may be produced within the receptacle in the ice freezing compartment of a refrigerator. The panlike receptacle I is generally rectangular in shape and is molded in one piece from polyethylene or equivalent plastic material to provide a generally :dat bottom II terminating in parallel side walls I2 and rear and front walls I3 and I4 which are integral with the bottom and extend continuously around the four sides of the tray. The bottom of the receptacle is relatively thin and after merging into the side and end walls the latter preferably increase in thickness in the direction of the upper edges thereof. walls I2 and rear end wall I3 terminate at their upper edges in a thickened edge I5 which extends continuously around three sides of the tray. The front end wall Il increases in thickness and merges into a handle I6, which may be grasped to remove the tray from the refrigerator compartment, and the front ends of the edges I5 merge into this handle. At the junctures between the ends of the wall I4 and handle I6 there are reinforcing webs ISa. Midway of the wall I4 an additional reinforcing web or gusset I6b is provided.

The pan-shaped receptacle III is molded to provide in its bottom a central longitudinal rib I1 which is preferably substantially V-shaped and extends upwardly from the plane of the bottom a distance materially less than the height of the receptacle. The rib I'I has a portion Ila, as shown particularly in Fig. 2, which continues upwardly into the front wall I4 and progressively diminishes in depth so as to disappear at the upper edge of the wall I4 where it merges into the handle I6. Similarly, the rib I1 has a portion IIb which continues into the rear end wall I3 and progressively diminishes in depth so as todisappear at the upper edge of this wall. The pan-shaped receptacle I0 is also molded to provide a series of parallel transverse ribs I9 in the bottom thereof which correspond in height to the rib I1 and, in like manner, are generally V-shaped in cross-section. Each transverse rib I8 intersects the longitudinal rib I'I and extends the full width of the bottom. At each end thereof each of the transverse ribs I8 has a portion I9a continuing into the side wall I2. Thus, as shown in Fig. 3, each upwardly extending portion I8a of each transverse ribprogressively diminishes in depth and disappears at the locality of the edge I5. From the foregoing it will be seen that the marginal edge I5 and handle I5 extending around the upper edge of the tray receptacle together with the longitudinal and transverse ribs provide a stiifening means for the tray receptacle enabling it to retain its shape, or substantially so, when filled with water so as not to buckle upon lifting the tray with its contents from one end while the tray is being carried to or from the refrigerator.

In accordance with the present invention the pan or receptacle III is adapted to receive the grid or divider member I9 for the purpose of molding or forming ice cubes or frozen blocks in suitable number in accordance with the size desired. In the present instance the grid I9 is designed so as to form sixteen ice blocks, although it will be understood that the grid may be designed to produce a smaller or larger number thereof. As in The sidethe case of the pan or receptacle Il, I prefer to utilize an injection molding process for producing the grid or divider member I9, and as illustrated particularly in Fig. 4 this member comprises a central longitudinally extending divider strip 2o integrally joined to and intersected by transverse right-angularly extending divider strips 2 I. Each of the divider strips 20 and 2l preferably diminishes in 'thickness toward the upper edge thereof so as to have tapering side walls. These divider strips all merge integrally into one another and at the locality of their intersections are joined by fillets 20a which serve to hold the divider strips permanently in correct relative positions. Since the divider strips are substantially thicker at their lower edges they form restricted bottom openings of less areas than the areas of the openings between the divider strips at the upper edges thereof, and as a consequence provide means for restraining the ice cubes within the spaces between the divider strips against removal through these restricted openings.

From the foregoing it will be noted that the strips or members 20 and 2| forming the divider or grid I9 taper somewhat in the direction of the upper edges thereof, and in addition the side and end walls of the pan or receptacle I0 also are tapered or inclined, this construction facilitating the removal of the ice blocks from the grid without necessitating the removal of the latter. The 'ends of the divider strips 20 and 2| are tapered so as to conform to the inclination of the side and end Walls so as to cause the grid to fit rather snugly within the pan or receptacle III.

In accordance with the preferred embodiment the grid strips 20 and 2l are arranged so as to extend in vertical alignment with the ribs I'I and I8, so that when the grid is inserted within the pan the lower edge of the grid 20 will rest upon the upper edge of the rib I1 and the grid strips 2| will rest upon the upper edges of thetransverse ribs I8. By virtue of this construction the height of the grid may be shortened and the ice forming spaces will be formed between the sides of the grid strips, the ribs I'I and I8, and the bottom II of the receptacle.

In preferred practice the pan shaped receptacle I 0 and the grid I9 are each formed in a single injection molding operationl from polyethylene plastic or equivalent material. Polyethylene is particularly adapted for use in the fabrication of the present ice tray for the reason that this material has a wax-like surface which is non-wettable by water and, hence, inhibits the adherence of ice thereto. Polyethylene is not only tough,

, flexible and substantially unbreakable, even under conditions of hard usage, but will also yield under tension in order to compensate for the expansion of ice upon freezing. After the formation of ice cubes in the tray the frozen contents together with the grid member may be readily loosened from the bottom and side walls of the.,

pan or receptacle I0 upon grasping the ends of the pan and torsionally twisting or flexing the same. This action will loosen the grid and its contained ice cubes as a unit permitting the removal thereof from the pan. One simple method of removing the grid and ice cubes as a unit from the pan consists in inverting and placing the pan upon a table top and then either.

twisting or flexing somewhat the ends of the pan or pressing -upon the bottom thereof so as to separate the pan from the grid and its ice cubes.

On the other hand, if a few cubes are desired, the pan may held rightside up and pressure applied by the thumbs to the bottom of the pan beneath the ice cube to force it upwardly or outwardly from the pan without removing the grid. This method of ejecting the cubes individually from the pan and grid is possible by reason ofthe thin iiexible character of the bottom wall of the pan and the taper given to the side walls of the pan and grid.

The construction of the present ice tray not only permits its fabrication from flexible or yieldable polyethylene material but also enables the bottom of the pan to be made relatively thin so as to accelerate freezing of the water. I prefer to form the bottom I I of the pan or receptacle I Il with wall thicknesses ranging from approximately .030 to .040 of an inch with the wall thickness of the upright sides and ends of the pan increasing progressively so as to have a uniform thickness of approximately .073 to .093 of an inch. This construction together with the ribs I1 and I 8, which continue into the side and end.

walls, not only aii'ords suilicient rigidity to the tray, irrespective of the thin bottom thereof, so as to render it substantially form-sustaining even when iilled with water, but also ensures a high degree of iiexibility to the bottom and side wallsv in the areas between the ribs which facilitate removal of the cubes and also accelerates freezing thereof. Although the thickness of the bottom II of the tray receptacle preferably falls within approximately the foregoing range. it will be understood that a wall thickness from apf proximately .020 to .065 of an inch will give good results. In the fabrication of relatively large trays the thickness of the bottom II may range from approximately .040 to .065 of an inch whereas in smaller size trays the bottom may be molded to a thickness. from approximately .020 to .032 of an inch. 'I'he divider strips 2l and 2i preferably taper to substantially the width of the upper edges of the ribs I'I and I8 and it will be noted that these ribs are formed with nat upper edges so as to facilitate seating of the divider strips thereon.

I claim:

1. A liquid freezing tray comprising a panshaped member having a bottom and surrounding upright side walls, said bottom having a longitudinalribintersectedbyapluralityoftransverse ribs, and a removable grid member within said pan-shaped member and comprising connected longitudinal and tramverse divider strips havingtheirloweredgesensagingsaidrimsaid strips increasing in thickness from their u edges toward the lower edges thereof.

2. In a liquid freezing tray, a pan-shaped member formed of polyethylene plastic having a bgtom and surrounding upwardly and outwardly clined side walls diminishing in thickness toward the bottom, the latter being formed with longitudinal and transverse intersecting ribs projecting upwardly at their ends in to the side walls.

3. Inaliquid freesingtray.apenshapedmem surrounding upwardly and outwardly inclined side walls diminhing in thicknesstowardthebottathelatterbeing formed with longitudinal and tramverse intersecting ribs projecting upwardly at their ends into thesidewallaandagridmemberwinn said pan-shaped member comprising intersecting longitudinal and tramverae divider strips rut- 4. In a liquid freezing tray, a pan-shaped member having a bottom and surrounding upwardly and outwardly inclined side walls diminishing in thickness toward the bottom, the latter being formed with longitudinal and transverse intersecting ribs projecting upwardly at'ther ends into the side walls, and a grid member within said member comprising intersecting longitudinal and transverse divider strips resting upon said ribs, the walls of said strips increasing in thickness toward their lower edges.

5. In a liquid freezing tray, a. pan-shaped member having a bottom and surrounding upwardly and outwardly inclined side walls in thickness toward the bottom, the latter being formed with shallow longitudinal and transverse intersecting generally V-shaped ribs extending upwardly from said bottom and of substantially the same height at the regions of the merger thereof.

6. In a liquid freezing tray, a pan-shaped member having a bottom and surrounding upwardly and outwardly inclined side walls diminishing in thickness toward the bottom, the latter being formed with shallow longitudinal and transverse intersecting generally V-shaped ribs extending upwardly from said bottom, said member being formed'of polyethylene plastic and said bottom being thinner than the upper edges of the side walls.

7. In a liquid freezing tray, a pan-shaped member having abottom and surrounding upwardly and outwardly inclined side walls diminishing in thickness toward the bottom. the latter beingv formed with longitudinal and transverse intersecting generally V-shaped ribs extending upwardly from said bottom, said member being formed of polyethylene plastic and said bottom being thinner than the upper edges oi' the side wallsandhavingathicknessransingfromapproximately .020 to .065 of an inch.

8. In a liquid freezing receptacle, a flexible panshaped member having a bottom and surrounding upright side walls, said bottom being formed with shallow upstanding longitudinal and transverse intersectingribshavingextensionsattheends thereof extending upwardly into said side walls abovesaidribaandaiiexiblesridwithinsaid member and comprising longitudinal and trans- `verseintersectingverticaldivider-stripsengaging saidribsand extensions.

JOHN EROETHEL.

REFERENCES CITED Thefollowingreference'sareofrecord-inthe meofthispatent:

UNITED STATE n PATENTS UIHER REFERENCE Chemical Industries, vol. 54,page 371, March Plastics," vol. 25, pp. 73-80, February 1948. v 

